Telephone-transmitter.



- 'J. COLLINS. TELEPHONE TRANSMITTER. LPPLIOATIOH FILED 00'1.21, 1912.

- WM). swoon [oz Patentd July 15, 1913.

W. n. oonm MAL-million,

Application filed heir/oer .21, 191:?

Y 1') all whom 1' i llbdj/ come m.

lie it known ll 1-17 I, JAIRUS Commie, :1, citizen oi the United Slates,residing at Qua-her City oouniy oi? Guer'nrey, and El oi Ohio have inented certain new and mo fol lln provcmonl's in T4 ephoiio llransniil1-lors; and I do declare the iollmving to bo full, clear, and exactdesoription oi lihe invention, 6; oh no will. enable others skilled inthe ml to which it appertaino to make and iii-1o rho r-szmie,reforeiiice being ho d to he nooomponying clrzlwilogs and 110 (helelilers and figures of reference marked lihercon, which formal part ofthis specilication,

invention relates to iniproveinenls in lielphone transmitters.

Oneobjcct is in so form the vilnolory (ii-w phmgm ask/0 permit its beingquickly sombled and disassembled, providing on even lension upon theentire circumference, and doing away with the usual. soft rubberonshioning bond Anolhor object of my invention is to pro vide al'ronsmill'or oi the type i n which both eleolzrodcs and theircorrelated ports supported entirely upon the diaphragm, and in which thocasings: containing ihe electrodes is supported upon the diaphragm onlyhymn flexible insulation. plate which forms the front cover of thecasing *"he front clecnode being iigidly nupporlrd with Joel lo thediaphragm. I my construction, o rear elec node in inniniton'iedpractically siltoiionar r by the force of inertia, while lhe front olor'lgroder being oll' icl'ied rigidly to the l'lllilllk' ing diaphragm,rdoeives all of the vibrnlxions of the latter, and transmits them to there sis-lance varying medium.

In the dnowing: Figure 1 is aside View, porily in section, showing thegeneral orra-ngernenla of my invon-tion. E2 is :1 diamonds oroes seoiionthrough the lransproper, and a, portion of the dim 'oisrogi'o, llheparts being shown in nmgnilied roportions for lhe sal e of cleorinaos.hi l. 0 is View similar to ll'ig. 2 but showing one portion of thetrorihmiltor separoie from the other portion, and the resistancevarying.

medium removed.

The same reference chomoiers indicole the some norl's in each of theviews.

l. illnwroiced in v invention. on applied o tho llTll-lilfilunilli 21 n1look sch, ii heino; the

Specification of Lotters Eetont.

lPn agonhcd July 151, 1913.

Seriiil l lo. 7%,928.

upright of such a set. The rear portion 13 oi" the transmitter is formed01 metal, asv

usual, the faceplate 7 being formed also of inolial, and {ii-inched tohe rear portion 6 by moons of lugs 8 and screws 9, as shown, or by anyother suitable means. Into the facephil'e is threaded mouth-piece 10 ofthe oii-iilinnry type. The vibratory diaphragm 11 19 of metal or othersnil'oble material, and is hold; forwardly iii its periphery to form :1continuous flange 12 extending entirely around the diaph *agm, whichflange is adapi'ed to lightly engage against an inner shoulder 13 formedupon the back of the faooploie l and cxljendii'ig entirely around thesame. This means of scouring the diaphrogin lo the face-plate forms animporl'onlfeature of my invention, as the parts may be readily assembledor disassembled merely by the use of slight pressure upon one or theother side of the diaphragm, and the use of The customary soft rubbercosh? ioning pad is avoided.

The resistance varying medium, prefer obly carbon granules, is incloscdWithin a (1156 of drum shape of which the back elecl'JOflZ) 1. 1 may beutilized to form the rear oloonro. The cylindrical portion of the casingis composed. of a ring of hard rubber or other insnhrling imoteriolalhe'electrode 14 5: nd ring 15 being securely fastened together by onannular inecol "in-ember A similar inoiol nienibc 1i" surrounds the ring15 upon. the other Side and holds loosely in place l'he insulationplate 1. which ll prefer to make of ln rd rubber, but for which mica issuitable. The front electrode 19 is of a diameter sligh less than theinside diameler of the ring 15, thus preventing any friction between thetwo parts when the device is in use. Carbon granules 20 are placedbetween the electrodes 14 and 19, and noa y fill l'he Space betweenthese two elements. ln order to prevent these granules from crowdinginto the annular space between the electrode 19 and the ring 15, andbetween the electrode 19 and the plate 18, thus preventing the properoperation of the do'vi'ce, 1 place cotton fiber 21 in. said annuspoce.However, Ido not wish to limit myself to the use of cotton fiber forthis nin'g iooe, it wi I be readily understood illlfillfi any dollygiiiclring material which will not form an' appreciable resistance tothe movement ,of the parts upon'each other, will be satisfactory. It isadvisable that a space .be left between the plate 18 and the electrodeutilized to hold the bolt 23 and the casing diaphragm 11.

' wire 27 to the rear-.portion 6 of the trans mitter the current beingconducted from this point through the metallic members 6, 7, and 11, andthrough the screw-bolt 23 to the front electrode 19. An insulationbushing 28 protects the wires t'rom'possible damage and consequentshort-circuit through contact with the sharp edges of the hole in therear portion 6 of the transmitter.

Particular attention is called to the fact that the plate 18 is smallerin diameter than the inside diameter of the annular member 17, and alsothat it is thinner than the space between the rubber ring loand thesubstantially vertical portion 29 of the annular member 17, when saidannular member forced up firmly against the shoulder 30 of the rubberring 15. By reason of this construction, that part of the casing whichincludes the back electrode 14, ring 15 and annular members 16 and 17,hangs loosely from the upper edge of the insulation plate 18, permittingthis plate 18 to move back and forth within the casing in response tothe vibrations of the diaphragm 11, while the casing, (including thatpart shown at the left in Fig. 3'and the annular member 17 remainspractically stationary, due to the fact that the inertia of thecmnparatively heavy casing overcomes the tendency of the latter to movewith the motion of the plate 18 in response to the vibrations oi thedia- ')hragm. I, therefore, have a substantially fixed electrode ltuponone side of the carbon granules, and an electrode 19 upon the other sideof the granules vibrating with the This motion acts upon the granules tovary the resistance of the latter, causing variations in the intensityof the current passed through the granules, thus electricallytransmitting sound, as will be well understood bv those skilled in theart.

to'said ring upon one side the periphery of.

the latter, a vibratory diaphragm, an insulation plate and a frontelectrode, both sup ported centrally upon said diaphragm, an annularmember clamped upon said insulation ring on. the side opposite said backelectrode, said annular member having an in-turned flange looselyengaging said insulation. plate, the latter being of a diameter slightlyless than the inner diameter of said annular member whereby the saidannular member, with the insulation ring and back electrode, hangsloosely upon saidplate, and a resistance varying medium located withinsaid insulation ring between the electrodes.

In a telephone transmitter, an insulation ring, a back electrodesecurely fastened to said ring upon one side of the periphery of thelatter, a vibratory diaphragm, an in sulation plate, a front electrodeof a diameter less than the inside diameter of said ring, saidinsulationplate and front electrode being both supported centrally upon saiddiaphragm, an iinnular member clamped upon said insulation ring on theside opposite said back electrode, said annular member having anin-turncd flange loosely engaging the said insulation plate, the latterbeing of a diameter slightly less than the.

inner diameter of said annular member whereby said annular member, withthe insulation ring and back electrode, hangs loosely upon said plate,so't'tpacking arranged within the annular space between said ring andfront electrode, and a resistance varying medium located within Saidinsulation ring bet-ween the electrodes.

in testimony whereof I allix my signature in presence of two witnesses.

JAIRUS COLLTNS.

\Vitnesses EUGENE Benson, N. D. Bonron.

